[PATCH V3 2/9] mac80211: add multiple bssid support to interface handling

John Crispin
2020-08-12T15:01:05Z

When bringing up multi bssid APs we need to track the parent-child relation
of non-transmitting and transmitting VAPs. This patch checks the above by
using a linked list to track the relations. The patch also ensures that
when a non-transmitting interface is closed the transmitting one is also
closed.

Signed-off-by: John Crispin <john@phrozen.org>
---
include/net/mac80211.h | 13 +++++++++-
net/mac80211/cfg.c | 54 ++++++++++++++++++++++++++++++++++++++++++
net/mac80211/debugfs.c | 1 +
net/mac80211/iface.c | 7 ++++++
4 files changed, 74 insertions(+), 1 deletion(-)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index f0ae718633d2..b409a5f1026c 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1649,6 +1649,9 @@ enum ieee80211_vif_flags {
* write-protected by sdata_lock and local->mtx so holding either is fine
* for read access.
* @cca_color: the color that we will have after the change.
+ * @multiple_bssid.parent: a non-transmitted bssid has a transmitted parent.
+ * @multiple_bssid.list: linked list for tracking parent - child relations.
+ * @multiple_bssid.non_transmitted: Is this a non-transmitted bssi
*/
struct ieee80211_vif {
enum nl80211_iftype type;
@@ -1675,6 +1678,11 @@ struct ieee80211_vif {
bool rx_mcast_action_reg;

bool txqs_stopped[IEEE80211_NUM_ACS];
+ struct {
+ struct ieee80211_vif *parent;
+ struct list_head list;
+ bool non_transmitted;
+ } multiple_bssid;

bool cca_active;
u8 cca_color;
@@ -2326,7 +2334,7 @@ struct ieee80211_txq {
* @IEEE80211_HW_TX_STATUS_NO_AMPDU_LEN: Driver does not report accurate A-MPDU
* length in tx status information
*
- * @IEEE80211_HW_SUPPORTS_MULTI_BSSID: Hardware supports multi BSSID
+ * @IEEE80211_HW_SUPPORTS_MULTI_BSSID: Hardware supports multi BSSID in STA mode
*
* @IEEE80211_HW_SUPPORTS_ONLY_HE_MULTI_BSSID: Hardware supports multi BSSID
* only for HE APs. Applies if @IEEE80211_HW_SUPPORTS_MULTI_BSSID is set.
@@ -2335,6 +2343,8 @@ struct ieee80211_txq {
* aggregating MPDUs with the same keyid, allowing mac80211 to keep Tx
* A-MPDU sessions active while rekeying with Extended Key ID.
*
+ * @IEEE80211_HW_SUPPORTS_MULTI_BSSID_AP: Hardware supports multi BSSID in AP mode
+ *
* @NUM_IEEE80211_HW_FLAGS: number of hardware flags, used for sizing arrays
*/
enum ieee80211_hw_flags {
@@ -2387,6 +2397,7 @@ enum ieee80211_hw_flags {
IEEE80211_HW_SUPPORTS_MULTI_BSSID,
IEEE80211_HW_SUPPORTS_ONLY_HE_MULTI_BSSID,
IEEE80211_HW_AMPDU_KEYBORDER_SUPPORT,
+ IEEE80211_HW_SUPPORTS_MULTI_BSSID_AP,

/* keep last, obviously */
NUM_IEEE80211_HW_FLAGS
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 37a218b89c9a..50a219d8a2cc 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -111,6 +111,36 @@ static int ieee80211_set_mon_options(struct ieee80211_sub_if_data *sdata,
return 0;
}

+static int ieee80211_set_multiple_bssid_options(struct ieee80211_sub_if_data *sdata,
+ struct vif_params *params)
+{
+ struct ieee80211_local *local = sdata->local;
+ struct wiphy *wiphy = local->hw.wiphy;
+ struct net_device *parent;
+ struct ieee80211_sub_if_data *psdata;
+
+ if (!ieee80211_hw_check(&local->hw, SUPPORTS_MULTI_BSSID_AP))
+ return 0;
+
+ if (params->multiple_bssid.non_transmitted) {
+ parent = __dev_get_by_index(wiphy_net(wiphy),
+ params->multiple_bssid.parent);
+ if (!parent || !parent->ieee80211_ptr)
+ return -EINVAL;
+ psdata = IEEE80211_WDEV_TO_SUB_IF(parent->ieee80211_ptr);
+ if (psdata->vif.multiple_bssid.non_transmitted)
+ return -EINVAL;
+ sdata->vif.multiple_bssid.parent = &psdata->vif;
+ list_add(&sdata->vif.multiple_bssid.list,
+ &psdata->vif.multiple_bssid.list);
+ sdata->vif.multiple_bssid.non_transmitted = true;
+ } else {
+ INIT_LIST_HEAD(&sdata->vif.multiple_bssid.list);
+ }
+
+ return 0;
+}
+
static struct wireless_dev *ieee80211_add_iface(struct wiphy *wiphy,
const char *name,
unsigned char name_assign_type,
@@ -136,11 +166,35 @@ static struct wireless_dev *ieee80211_add_iface(struct wiphy *wiphy,
}
}

+ if (type == NL80211_IFTYPE_AP) {
+ err = ieee80211_set_multiple_bssid_options(sdata, params);
+ if (err) {
+ ieee80211_if_remove(sdata);
+ return NULL;
+ }
+ }
+
return wdev;
}

static int ieee80211_del_iface(struct wiphy *wiphy, struct wireless_dev *wdev)
{
+ struct ieee80211_sub_if_data *sdata;
+ struct ieee80211_vif *child, *tmp;
+
+ sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);
+ if (sdata->vif.type == NL80211_IFTYPE_AP) {
+ if (!sdata->vif.multiple_bssid.non_transmitted) {
+ if (!list_empty(&sdata->vif.multiple_bssid.list))
+ list_for_each_entry_safe(child, tmp,
+ &sdata->vif.multiple_bssid.list,
+ multiple_bssid.list)
+ dev_close(vif_to_sdata(child)->wdev.netdev);
+ } else {
+ list_del(&sdata->vif.multiple_bssid.list);
+ }
+ }
+
ieee80211_if_remove(IEEE80211_WDEV_TO_SUB_IF(wdev));

return 0;
diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c
index 54080290d6e2..5d5c9185755a 100644
--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -408,6 +408,7 @@ static const char *hw_flag_names[] = {
FLAG(SUPPORTS_MULTI_BSSID),
FLAG(SUPPORTS_ONLY_HE_MULTI_BSSID),
FLAG(AMPDU_KEYBORDER_SUPPORT),
+ FLAG(SUPPORTS_MULTI_BSSID_AP),
#undef FLAG
};

diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 8060cdc102d4..e6397d0c788d 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -810,6 +810,13 @@ static void ieee80211_do_stop(struct ieee80211_sub_if_data *sdata,
bool cancel_scan;
struct cfg80211_nan_func *func;

+ if (sdata->vif.type == NL80211_IFTYPE_AP &&
+ sdata->vif.multiple_bssid.non_transmitted)
+ /* make sure the parent is already down */
+ if (sdata->vif.multiple_bssid.parent &&
+ ieee80211_sdata_running(vif_to_sdata(sdata->vif.multiple_bssid.parent)))
+ dev_close(vif_to_sdata(sdata->vif.multiple_bssid.parent)->wdev.netdev);
+
clear_bit(SDATA_STATE_RUNNING, &sdata->state);

cancel_scan = rcu_access_pointer(local->scan_sdata) == sdata;
--
2.25.1